hostapd: Fix aliasing violation

Change-Id: I1661f1e50959165542aed00374467715dc26d847
Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>

driver_wext: declare wext private lib functions up front else 4.2 build will fail

Change-Id: I6d6c7d5153738b0ddd4d217a513397987eeb7434